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I originally posted this to a Camry thread, now I've moved it to a better one. I'll link in the references once I've tracked them down. Most of it is pulled from Hobbits site (or as Marc's coined it, "The gospel according to Hobbit").

This is Prius based, but has some general tenants in it too. I'll try to bracket Prius stuff in red.

Original:
Whoo hoo... you asked.....

HSD (Toyota-Hybrids) P&G tech by Dan...

1) Pump up the tires.
2) Put in a SGII, so you can watch coolant temp.
3) Set the screen to Energy display (you see the 4-wheels picture)
4) Set the spedo to KPH (since that is what Dan uses)
5) Set the SGII to read degC (since that is what Dan uses)
6) Figure out how to shift the car into neutral
7) Remember, there is no FAS in an HSD, you have to talk HSD into doing it for you.
8) Decode "AS" to read Auto-Stop (borrowing Honda's term since Toyota hasn't defined one).

Starting:
Plan your route / parking so that you can coast after getting a running start. To get the running start, wait for a clearing, then press the brake and get ready to hit "POWER". There will be about a 500ms delay between power up and when you can shift into D/R, so be prepared. Once powered up, you have about 10-15s of EV before the ICE lights. You can veto the lighting of the ICE if you can get into N before it happens. So EV for < 15s, then shift to N. Coast as long as you can before you go into D again. Once you do, HSD will light the ICE and you'll be in Sage 1 warmup.

Warmup:
This bites, but I don't know how to get out of it. For the next minute or so (on cold engine) the ICE will run, no matter what speed your at. AS is quasi-disabled so you might still idle at stops, so fall back on the planning you made when you parked to get through startup-EV and warm up without stopping. This is where you start watching the cWT (coolant water-temperature) on the SGII. The goal is to hit 70c. Most cars start in the morning with cWT of 20c - 30c. AS is disabled until you get to 40c. Once at 40c the ICE will shut off when you come to a complete stop (might take 10s, but it will stop). The best thing you can do in warmup is NICE-on (since FAS is out). So whenever you don't need to accel, throw it into N. Remember to put it back in D for braking or when at at a full stop that the battery can charge and AS (if any) can engage.

S3 -vs- S4 operation:
AS is not fully enabled until a zero-speed AS happens above 70c. This means that you come to a stop with the engine running, it idles, then cuts off because your not moving. Once this happens your in S4 (full AS) until the temp < 70c again. Just try to memorize that point.

S3 Cruising:
If you have a route without any stops (since you planned well), you can't force S4, so you'll have to cruise in S3. This is fine, but all your pulses have to end between 55 kph and 65 kph (keep it 56-64 to be safe). If your in S3 that is the only time cruising AS is enabled. So I pulse up when I hit 50kph and glide when I hit 65kph. But once I light the ICE I have to get to 55kph for the engine to cut. If I have to terminate a pulse early (cuz someone cut me off), I'm stuck with the ICE on till I get back up to speed. But once you coax an AS, the ICE will stay off till you get "on" the gas. Do be aware that (as of this morning) I've discovered that S3 glides fill fail if you've never (since starting) had your engine above ~2000 RPM. So on my first S3 glide, I usually let the RPM shortly crest 2400.

S4 Cruising:
If you've fallen upon S4, or you've forced S4, AS is fully armed. HSD will kill the ICE whenever your "off" the gas and your speed is < 65kph. Above 65kph HSD will always turn the ICE, so you have to plan to stay in that window.

Gliding:
In S3 (in the right window) or S4, AS will kill the ICE when your "off" the gas, problem is it also engages regen braking. You can monitor AS by watching RPM on your SGII. Whenever it dips below 960 RPM, it's killing the ICE (should see it go to 0 in < 1s). There will be some false indicators in S3, but 0 RPM is proof positive. Now once you've AS'd you don't want regen braking to rob your glide, so you can either throw it in N (disengage regen braking) or "feather" the gas to get to the neutral position. You should see the energy display go to black when you hit it. If you put it in N remember to go back into gear before you brake so you can store some of that momentum as regen.

Forceing S4.
If your at a ICE-off full stop in S3 and you want to force S4, you can do it by pressing the gas and brake at the same time (press brake harder) till the ICE lights. You should see the RPMs pop up to 1200 then cool off to around 1100. Stay off the gas and on the brake for a few seconds and the ICE should cut out. You've now forced S4 since you AS'd while at 0kph

Stealth:
Not always good for FE, but if your in S3 and you have a short strech that you don't want to pulse up through, you can feather the gas and you should see all yellow (no orange) arrows on the energy display. This is a thin window, so if you press too hard you will light the ICE, but it can extend a glide or save you from having to pulse up.

Pulse:
While you accel look at the yellow arrow between the battery and generator. Try to position your acceleration where there is no arrow coming from the battery. At low speeds 0-35kph, your best off just golf-carting. If you accel gently from a stop you will run on all electric till you start to request too much juice. Once you light the ICE and your > 35kph, I just look at RPM. I find it's easy to hold dead-band (no arrows b/t battery and generator) below 35kph, but above 35kph, holding deadband gets the RPMs too high.

Warp-Stealth:
While riding at highway speeds, you can stealth on downhill/netural stretches of road. This steath is a MUCH narrower window to hit than the < 65 kph stealth. To hit it at speed let off the accel and then lightly (and I mean lightly) touch it. As you gradually (and I mean gradually) increase pressure you should see the regen go to either all black or all yellow. Thats it. Your SGII will now report that your burning gas (MPG of 150 not 9999), but it's basing that on the fact that the engine is turning. Since the SGII isn't hooked to the injectors, it doesn't know that fuel has been cut. You should see your RPM at 960 when your in this window. On my commute I use this on all the downhill grades as a decel glide and pulse up around 75kph if my tail is clear (Ref: Hobbit's SW P&G writeup)

RPMs:
It's best to keep the RPMs in a sweet spot. This is 1200 < RPM < 2200 for city and 1400 < RPM < 2400 for highway. Personally I try to always keep it 1400 < RPM < 2000 cuz that is easier for me to remember.

Cruise Control:
On long trips (not my commute), it may be difficult to employ Stealth-Warp pulse and glide, so I use Cruise Control on occasion. Problem with CC is that it will rev the engine if it falls off it's target speed or perform regen braking if it's overshot it. So I've developed a CC method to try to guard against it. It's kinda the opposite of DWL but it serves the same purpose. So with the CC set to 88kph (55mph) I scan the road for any upcoming hills. If I see one, I leave CC on and slowly get on the gas to build speed before I hit grade. I'll keep the RPMs at 1900 or so on this pulse and judge wether I gain or loose speed on the hill to adjust. My goal is to hit the top of the hill b/t 88-99 kph. When I hit the top of the hill I can feather the pedal into a nice stealth-warp on the down-grade. If I fall below target on the downgrade, CC will adjust throttle less violently than it usually does on an uphill grade. If you watch your speed you should know when CC is about to panic and get on the gas. Your goal is to have this happen on neutral or downward grades. If it's gonna happen on an uphill grade, play with the throttle before you fall off target so the engine is already at a good RPM when CC tries to do it's adjustment. The main goal here is to keep CC from panicking. This method is the main reason I went to KPH. Running with CC set to 88, I won't be off target till I hit 86. So I consider 87 a warning for me to take over before CC does. I will either disengage CC or get on the gas before CC does. This is a quirk of the US models. The CC is set (internally) on MPH target speeds. So your at 55 MPH when your at 87 or 88 KPH because of rounding. Usually gives you just enough buffer.

Putting it all together:
Plan a route that lets you spends as much time as possible between 55kph and 65kph (35 - 40 mph). This is where HSD nets you > 100mpg. If you you know you have segments < 55kph, force S4. You don't want to be stuck in S3 with ICE-on with a steady flow of traffic at 50kph. If you have to cruise above 65kph, look at Hobbit's site. He's found some good tricks like Stealth-Warp and Throttle-Control that help to bang out 60+ MPG at speed. If you use CC try to be aware of when it will take drastic action and either cancel it, adjust your driving to meet the terrain.

11011011

Nice write-up Dan! I have just a few things to add/comment on. :) (Warning: probably PII-specific)


4) Set the spedo to KPH (since that is what Dan uses)
5) Set the SGII to read degC (since that is what Dan uses)


:D


Once powered up, you have about 10-15s of EV before the ICE lights. You can veto the lighting of the ICE if you can get into N before it happens. So EV for < 15s, then shift to D. Coast as long as you can before you go into D again. Once you do, HSD will light the ICE and you'll be in Sage 1 warmup.


I didn't know about the N for "ICE startup veto" - cool! I'll try that next trip (actually I have to back out of the garage/driveway but it's downhill, so I should be able to go R for a few seconds to N, coast, shift to D?) Of course the EV button mod lets you veto as long as you need to (SOC/battery temp dependent). I think the normal power-on-to-ICE-light is 8 seconds unless you do something.


AS is disabled until you get to 40c. Once at 40c the ICE will shut off when you come to a complete stop (might take 10s, but it will stop).


Actually in my exp. these early S2 shut-offs are the quickest - S3 is where I might see 10sec and a rougher stop.

The best thing you can do in warmup is NICE-on (since FAS is out).

Pretty much no matter what you do you will be getting MPG of 1 to 1.5x MPH here, NICE-on or not. S1 sucks. :( I'd also add not accelerating strongly here - you'll just be drawing off the pack, which will just need to be replenished later. Wait for S2 for "normal" acceleration.

S3 Cruising: ...

This is by far where I've derived the most benefit from the EV switch. If I need to stop, great, S4 it is, otherwise keep moving and use EV to do pseudo-S4 P&G.

Do be aware that (as of this morning) I've discovered that S3 glides fill fail if you've never (since starting) had your engine above ~2000 RPM. So on my first S3 glide, I usually let the RPM shortly crest 2400.

Weird! I have not noticed this. 2000 RPM is pretty hard to do at low speeds, no?


S4 Cruising:
If you've fallen upon S4, or you've forced S4, AS is fully armed. HSD will kill the ICE whenever your "off" the gas and your speed is < 65kph. Above 65kph HSD will always turn the ICE, so you have to plan to stay in that window.


Occasionally, even in S4 I'll transition to a glide and won't get ICE-off, just red+green arrows and like 80 IMPG. This is most likely when I'm at 4 or 5 bars SOC. It might stay there through the whole glide (:mad:) or eventually go ICE-off (more likely if speed is around that magic 35MPH). EV switch to the rescue again :D

... or "feather" the gas to get to the neutral position.

The "feathering" is prius-specific?


Forceing S4.
If your at a ICE-off full stop in S3 and you want to force S4, you can do it by pressing the gas and brake at the same time (press brake harder) till the ICE lights. You should see the RPMs pop up to 1200 then cool off to around 1100. Stay off the gas and on the brake for a few seconds and the ICE should cut out. You've now forced S4 since you AS'd while at 0kph


Nice! Here's yet another use for the EV switch if you're coming from EV-assisted ICE-off in S3 (below 35MPH) to a stop - just deactivate EV once you get stopped. Now the ICE will come on for 5-10 sec, shut off, and you'll be in S4.


Pulse:
While you accel look at the yellow arrow between the battery and generator. Try to position your acceleration where there is no arrow coming from the battery. At low speeds 0-35kph, your best off just golf-carting. If you accel gently from a stop you will run on all electric till you start to request too much juice. Once you light the ICE and your > 35kph, I just look at RPM. I find it's easy to hold dead-band (no arrows b/t battery and generator) below 35kph, but above 35kph, holding deadband gets the RPMs too high.


Are you "golf-carting" all the way up to 35kph when in city conditions? My preference is to let the ICE back in if I've got any kind of significant accel. Otherwise I just run down the pack too quickly.

Also if you've done some extra-long glides or added a little EV here and there you might want red+green arrows on your pulse just to recharge the pack.


Warp-Stealth:
While riding at highway speeds, you can stealth on downhill/netural stretches of road. This steath is a MUCH narrower window to hit than the < 65 kph stealth. To hit it at speed let off the accel and then lightly (and I mean lightly) touch it. As you gradually (and I mean gradually) increase pressure you should see the regen go to either all black or all yellow. Thats it. Your SGII will now report that your burning gas (MPG of 150 not 9999), but it's basing that on the fact that the engine is turning. Since the SGII isn't hooked to the injectors, it doesn't know that fuel has been cut. You should see your RPM at 960 when your in this window. On my commute I use this on all the downhill grades as a decel glide and pulse up around 75kph if my tail is clear (Ref: Hobbit's SW P&G writeup)


As Hobbit mentions, the "window" you have is highly dependent on SOC - if you're running near 80% (down a long hill on the highway, for example) you may be able to WS for quite a while until the window narrows as your SOC returns to normal. Down below 50%, good luck. ;)


You don't want to be stuck in S3 with ICE-on with a steady flow of traffic at 50kph.


Sometime I will stop putting in shameless plugs for the EV switch, but this is one of its best uses. :D

Yeah, I'm gonna install the EV but I wanted to feel out all the features of the car before I did. There is still lots of room to learn. I never would have found the drop to N startup-veto if If I had it. Probably wouldn't have found out how to force S4 either.

I tried to do as little stage-talk as possible. Took me for ever to learn the stage stuff and I was trying just to give a high level view to touch on some of the details. So ice MIGHT shutoff quick > 40c (depending on what stage your in).

I'll add the bit about slow accel till in S2. I'll just say 60s so I don't have to introduce the topic of S1 or S2. I have found the MPG really spikes on NICE-on vs DICE-on.

Don't know if the temps are PII specific or not

The 2400 RPM first pulse warm-up is in alpha/beta right now. Seems to consistently fail if I do a slow pulse though. I'll label it as "in-dispute" for now.

I also get the S4 failure... happens on the exact same stretch of road. This is where my commute looses a passing lane, so people stack up behind me. When the do, I ev-extend my glide. Sometimes I push to hard and light the ice. Once lit it won't glide again for 30-60 seconds. I figured it was the 80 degC coolant pump coming on line.

Wayne had mentioned that feathering in the Camry was near impossible. So I include it as Prius specific.

I golf-cart as much as I can < 30kph. If I have a passing lane, they can pass. 35kph is pretty hard to hit without messing up the light timings, so I'll say 0-25kph as suggested golf-cart area. Problem with lighting the ICE below 20kph is that it's terribly inefficient. Took Marc's suggesting of always golf-carting then ease into an ICE-on acell. I'll fix the typo... I only deadband < 35kph, by 35 the rpms are at 1800, so from there on I'm on yellow+red recharg+acel. As far as EV'ing goes, I do as much as I can. My SOC usually holds at 3-5 soc. Coming off the highway I EV more, but once it hits 3 SOC EV is tricky. I reserve most of it for on quarter mile section that has 4 stop signs. If I'm not at S4 with 4 SOC there... my commute is pretty much shot!

I'll put the stealth-warp section under dispute. I've gleened that yellow arrows might be proof positive of fuel cut. Since my glides happen 2 miles into highway I'm usually at 6 SOC when I hit them.

OK... I'll edit up the changes in a bit...

I'm interested in other revisions since I'd like to get some of this up on wikipedia "Prius_Pulse&Glide".

11011011

Very good stuff Dan !!!

I almost regret not having installed the EV switch. I swear, my hands had the hitch (quite a few times over the last few months) to just order the darn thing. ;)

I think I'm goint to print this stuff out and place it inthe glove box with the user manual.

Cheers;

MSantos

That's a great writeup! The 2,000RPM requirement for a S3 glide never dawned on me but it makes so much sense. It gets me pretty much every morning!

The only item on this that should be up on Wikipedia is a pointer
to the real info, held on some website that you have actual
control over. Wiki-anything is too easy to vandalize; it's a
broken model.
.
_H*

Great stuff, Dan. Thanks for taking the time to organize it and put it on paper.

I'll have some comments to offer, but I want to take time to digest it all. I'll probably get back with you sometime tomorrow.

[Edit: Cross-posted at Priuschat. They have a bunch of CAN-view folks.]

Great detail Dan, thank you.

(or as Marc's coined it, "The gospel according to Hobbit").

I'm good for the occassional quip......not much else though ;)

I considered creating a new thread for my post, but in the end decided to tack on to this Prius thread.

I like the EV switch. I use it a heckuva lot. :) Given that I am pretty familiar with the "cannot switch to EV mode" message, I'd say I use it a bit too much. ;)

At any rate, you can imagine that I've become hypersensitive to SOC level, and efforts to maintain it. I've slowed 'er down by pulsing as much as possible, and at the very least do a "deadband pulse" (that's what I call it anyway, when orange & yellow arrows turn the wheels AND yellow arrow charges the battery). I also do a good deal of regen in EV mode in order to power 'er back up. I NEVER "assist". I'm mainly sacrificing speed for juice.

Unfortunately, I don't have CAN-view to monitor SOC levels and changes, and don't have any plans to purchase it. I considered it at one point, but decided that SGII would be sufficient. Also, I read that CAN-view actually can only be integrated into the early GenIII models ('04?, '05?), and I don't need yet another display in my '07. All I got are "the bars".

So.............questions for those with CAN-view and/or knowledge of battery charging:

Which stage delivers more charge to the battery?

(1) pulse
(2) "deadband with pulse"
(3) regen

I believe Hobbit has written that regen's charge is actually quite weak, although that might not mean "weaker".

What is the approx. rate of charge for these 3 stages?
Does the rate of charge increase or decrease as speed increases?
How do the rates of charge compare to the rates of loss while EVing?
Does the rate of loss while EVing at 10mph double at 20mph? Or more than double?

Any other questions I missed?

I realized today while trying to continually boost & use & boost & use SOC that................uh.................I really don't have a clue how to best boost SOC. I am, like many, at my best when I realize that I don't know what I don't know. :)

Thanks in advance for any replies.

Hi All:

___I just got called back into work for the night so I have to run but to go along with Marc’s questions; the Prius II draws a nice amount of current just sitting there booted up and in a Glide, another order of magnitude above that. I highly recommend staying the hell away from a dead band attempted pulse as you have to feed the need and every pulse is a perfect opportunity to do so.

___I am at a loss for the warm up stages given I have not had to deal with those in my short few hours behind any Prius’ windscreen. For maximum FE (distance traveled with a given minimum amount of fuel), a Pulse with the appropriate fill of the pack while using some EV to extend the glides and to get through the stop and crawls evident on any commute is the best thing going. Even a micro-pulse can be taken advantage of … I like to keep SoC in the lower end of the band for competition level hypermiling for reasons of my own design but that is just me.

___Never run her into Assist and never Regen if at all possible is the best advice this guy can give … The wild round trip numbers haven’t lied to me yet but your real world hours and experiences are far more detailed then mine will ever be.

___Good Luck

___Wayne

OK, here we go. Again, wonderful job. Just a few comments and a question or two, trying to avoid repeating Locutus' relevant comments.

General comments:
Assuming your target audience is predominantly American, you might consider also listing US measures. The purist in me supports the idea of a universal measurement system, but this realist, like many other Americans, has been using US measures for decades. Many (maybe most) would rather not have to make the conversions.

As you're making references to terms from the 5 stages paper, I suggest you either define the terms (golf-carting; S1, S2, ...) or link to the paper. You might also link other documents you've referenced, like Hobbit's papers.

Warmup:
From my observations, the 40c (OK, you've got me using Celsius for the moment!) threshold is not absolute. With a block heater-augmented "cold" startup temp at that level or above, the ICE still wants 30 seconds or more to warm up. So obviously there's more at work during S1 than just ICE temperature. Certainly the cat temp at a minimum, but I wonder if there's still more.

Forcing S4:
Help me out: What is the value in this? According to the 5 stages paper, the car will enter S4 from S3 on its own anyway with a full ICE-off stop.

Pulse:
To help those without added instrumentation, I floated an idea (http://priuschat.com/index.php?showtopic=32509&hl=load)on PriusChat for which I'm still seeking validation from those with a ScanGauge or other means of monitoring RPM. If you (and other Prius owners with the extra instruments) can take a look at that and provide me feedback, here or there, I'd appreciate it.

RPM:
Regarding the low end of the sweet spot: In a dialog (http://www.cleanmpg.com/forums/events-and-gatherings/t-the-big-southward-haul-page5-2698.html) with Hobbit he emphasized that it's not strictly low RPM that leads to engine loafing, it's low RPM + low load. For several weeks I've been watching LOD (engine loading) on the SG in the hopes that it, along with RPM, would help me get a handle on that. Without his instrumentation (and technical background), the best I can do is make some semi-educated guesses. When I know I'm in an efficient range, RPM-wise (say, 1800-2000 or so), LOD is around 50 + ~5. There are times I can let the RPM drop to about 1400, maybe a tad lower at lower speeds, and LOD stays at least in the mid-40s. So I'm guessing I'm still running somewhat efficiently. One thing I know is that the relationship between pedal and LOD is not linear; I can ease up some more and see a significant LOD dropoff into the 20s. I'm guessing (pretty confident, actually) I'm running inefficiently there. As for your proposed low end of 1200, that's pretty much past the dropoff point. About this, I'm also interested in hearing from other SG users.

Cruise Control:
The transition you've described from pedal to CC is essentially what I do on the highway if I'm running CC, but you've described better than I could. I like the term CC "panic." My main use for CC is a "safety net" of sorts on the highway. If traffic is heavy enough and hills steep enough that I'll create a safety risk creeping up the hills, I'll set CC at an absolute minimum of, say, 60. Then as I approach that speed going uphill I'll gradually give it more pedal to allow a smooth "panic-free" transition to CC. That serves a side benefit of giving my foot a short break from working the pedal.

Thanks again. Great job!

Take a look at this diagram (http://techno-fandom.org/~hobbit/cars/SAE-bsfc.gif) from an SAE paper. This is the
reason you don't see linear mapping from your foot to LOD --
throttle control is deliberately done that way, because it
*is* much more efficient! The real-life line is not quite
that rigidly linear, but the point is to climb the BSFC
"contour lines" as early as possible and stay on the peak.
.
This is the beauty of divorcing the loose nut from the
throttle flap -- you get to play these games. P&G simply
takes our best advantage of it.
.
_H*

Thanks to everyone for the input, there are quite a few revisions I have, and might put them into PDF. Might have to blow the dust off the blog to hold some of this stuff.

The biggest mystery right now is the RPM to enable S3/S4 glides? Still having unexplained glide failures after moving to a low RPM style. Jim got me thinking that it may be LOD not RPM. I'll be watching this afternoon.

Hobbit, I'll dig around and link in the to your site in the writeup (if you have no objections). If I write anything in wiki, I'll be sure to site sources and link in so readers can get the original source.

I did have a question on stage transitioning. In the 5 stage writeup, it says that S4 transition will happen when you come to a complete stop at the proper coolant temp. I've noticed that the engine also has to be running while stopped to transition to S4. Did I misread, or is my data incorrect?

Warp-Stealth, Do yellow (or black) arrows only at highway speed imply the injectors have been cut, or is this a false reading? Any indicators on the SGII that might make it definitive?

Consider this still a work in progress, and I'll work on refining the ideas further

Marc, Could you post the PC cross-post so I can keep up (may dig for it this evening). Also, where do you keep your SOC levels? Houston is flat and mine swing from 3 (shortly into warmup) to 6 (exiting freeway). I have some stop signs that I use bar 5 for. After that I might bleed off bar 4 and an EV-assist to catch a light timing, but without EV this can light the ICE and put you in the ditch.

Wayne, Agreed... I've started slower pulses if I need to feed my battery a bit, and steeper ones if my battery is full.

Jim, Great input thanks. I'll (begrudgingly) put in the MPH. I'm a big fan of KPH/degC because the numbers end up so nice and round. I think in degC at work all day too, so it's second nature.

force S4:
There is a spot on my commute (exiting the freeway) that some times lands me at a red light. For the last few months, stopped at that light @ 81c @ 6 SOC. I could never get S4 (testing on the accel into the turn). When I tried lighting the ICE for 5 seconds, Bingo! Can anyone confirm?

Pulse/RPM:
Great find... I'll spend some time digging through Hobbit's site to fill in my gaps. I can easily see that LOD could play a big part in this, so I'm moving my TPS gauge to monitor LOD.

11011011

Also, where do you keep your SOC levels? Houston is flat and mine swing from 3 (shortly into warmup) to 6 (exiting freeway). I have some stop signs that I use bar 5 for. After that I might bleed off bar 4 and an EV-assist to catch a light timing, but without EV this can light the ICE and put you in the ditch.

It's a bit all over the map right now, as I'm still playing with the EV switch. Also, as you well know............some days I can go without AC and some days I have to use it a bit.

In general, I'm 5 bars at home & 3 bars at work. The trip downhill to work involves significantly less pulsing and more opportunities for extended glides and such. I frequently get to a "cannot use EV at this time" denial by the end of my commute in. Going back uphill I power 'er back up.

Lately I've been fighting to get her back up to 5/6 bars, probably because of limited AC use. That led to my questions about SoC charging data.

Also, where do you keep your SOC levels? Houston is flat and mine swing from 3 (shortly into warmup) to 6 (exiting freeway). I have some stop signs that I use bar 5 for. After that I might bleed off bar 4 and an EV-assist to catch a light timing, but without EV this can light the ICE and put you in the ditch.

I'm at 6 probably 60% of the time, 5 30%, 4 5%, and >6 or <4 the remaining 5%. I have only let it drop to 3 or less a few times, and that was intentional (trying to EV all of a <1 mile trip). My thinking is any significant length of EV is worse than P&G because of conversion losses in dis/recharging - as well as limiting driver choice (i.e. forcing ICE-run) if 2 bars is accidentally hit. OTOH, if EV can be used to avoid something much worse, like an unnecessary warmup cycle, then I'll do that.

I did have a question on stage transitioning. In the 5 stage writeup, it says that S4 transition will happen when you come to a complete stop at the proper coolant temp. I've noticed that the engine also has to be running while stopped to transition to S4. Did I misread, or is my data incorrect?

From everything I've seen this is correct. If you're coming from >35 mph in stage 3 to a stop (ICE shuts down) and it's off when you stop, you will not go to stage 4.


Warp-Stealth, Do yellow (or black) arrows only at highway speed imply the injectors have been cut, or is this a false reading? Any indicators on the SGII that might make it definitive?


I don't know definitively, but I think this is also correct. WS (fuel-cut) = yellow arrows, SG IMPG is somewhere above 100 (often tracking MPH*3 or MPH*5 pretty closely), RPM settled around 960. Apply a little too much pedal, ICE will re-light, RPM will go above 1000, you'll go to red+green arrows and IMPG will drop below 100.

A little bit of input from my own observations:

I played with the RPM levels today during early S3 operation to see if breaking 2,000RPM is really necessary to get there. Interestingly enough I managed to get into normal S3 without getting much above 1800RPM. Of course, I noticed later that my tach is sticking so who knows if my observation means anything.

Regarding Warp Stealth: The tach I'm using runs off of the ignition signal, but I take that to be a fairly good indicator of injector activity as well. (One would not expect fuel to enter the combustion chamber if the spark plugs are disabled, right?) Generally, the tachometer dropping to zero correlates very well with the energy display's indication of warp stealth. 99% of the time that the engine re-lights (as indicated by the tach) the energy display also shows energy flow from the engine to the wheels & battery. The one situation in which this consistently fails is during warmup, when the engine is running no matter what. In that case the tach indicates engine activity but the energy display could be telling you anything.

Regarding SoC: These days I see very little fluctuation indicated on the battery display. I would estimate (read: make a WAG) that I have a nominal 6 bars 93% of the time, though I'm sure there's plenty of charge and discharge within that range. I very rarely see 5 bars of charge and only if I've really dipped into stealth mode for whatever reason. Call it 3% of the time or less but of course I'm just guessing. Seeing 7 or 8 bars happens more often but only as the result of a steep descent that resulted in too much speed to DWB safely. Call that 4% of the time or less, again a guess. The remaining 1% or less would be charge levels below 5 bars. I've only gotten below 4 bars once or twice as the result of high power demand during ICE warmup. I have since learned to baby it for the first minute so as not to deplete the battery appreciably. Otherwise my FE tanks while the system brings the charge level back up to nominal. I also do my best to stay off the pack for the sale of longevity. It may not matter but at least I **think** I'm doing my car a favor ;) .